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A High Frequency Trader's Apology, Pt 2

chrisstucchio.com

191–200 of 242 posts

Re: A High Frequency Trader's Apology, Pt 2

#191
post #167

Earlier quoted context omitted.

Be careful conflating Order and Price. The Order book is the current stack of buyers and sellers. Price is the last executed price. So when you say a price drifting upwards, that means that both buyers and sellers meet at that price. A corollary is that there were buyers and sellers at that price. In addition, this also means that the market could have also moved away from that price without a trade being executed (i…

You are trying to figure out a way in which I could be describing the current system, "correcting" me on all of the ways that I am not describing the current system, and then telling me that I am describing the current system. Take that blinder off. In the model that I suggest, the price is a number set by the exchange that trades are allowed to happen at, that moves in a predetermined fashion. Even if there are buye…

As I previously mentioned, please clarify the terms that you use. You use price as both last trade and order interchangeably, which is not correct and leads to confusion.

Define: Last Trade: amount that the trade last executed. Order: Bid or Ask order on the order books.

So, let's use your example of bid/ask $10.00/$10.05 and last trade of $10.03 You place a buy order at $10.20.

What you are suggesting is that the market sees if there is a sell order at $10.03. If there is, it executes. If there is not, it moves to $10.04. Again, it checks to see if there are any available sell orders at $10.04. If not, it goes to $10.05 and sees if there are any sell orders at $10.05. Since $10.05 is at the top of the order book, the trade executes.

Am I understanding this correctly? We both agree that in this given state, the trade will never execute at any other price other than $10.05.

So, you added that a seller comes along and places an ask order at $9.90. We now have a crossed book (bid greater than ask). So what price does this execute at? You suggest $10.03 because that was the last trade.

I would argue that this would be incorrect.

Let's take the scenario of a low volume security. Let's say it's a far out of the money or far in the money option. If you follow the market, you'll see that often times, the volume of these trades are maybe 1 or 2 trades per day. You will often see that the Last Executed price is often either above the bid/ask spread or below the bid/ask spread.

Take for example, CAT Jan 14 $110 PUT. Last trade is $20.45. Current Bid/Ask Spread is $21.80/$22.15. The last trade is almost 7% discount of current market value.

So, let's use this CAT example. Current order book shows $21.80/$22.15. Last trade is $20.45. A buyer comes in with an order at $25 and a seller comes in with an order at $20. What price gets executed?

>Even if there are buyers and sellers who are willing to trade at a different price right now, the exchange won't allow that trade to complete until the price set by the exchange goes into a range where that trade can happen. Please explain this sentence further. It makes little sense. The only way that buyers and sellers can trade is if they cross the bid-ask spread. If you are saying that two other people are willing to make a trade, that means that they've cross the bid-ask spread. In theory, the "price" that you mention should be in the middle of the bid-ask spread.

Let's use a concrete example: Going back to your $10.00/10.05 - last trade: $10.03 Am I understanding correctly that if someone places a buy order at $10.05 (ie order book $10.05/$10.05; last trade: 10.03) that that trade will not get executed? What happens in that scenario? Does the price rise to $10.04? (ie order book: $10.05/$10.05; "price": $10.04) In this case, the trade does not execute neither, even though two people are willing to trade at $10.05. So the "price" rises to $10.05 and the trade executes. If this is the case, as a trader, I would front run the seller at $10.05 and put a sell order at $10.04. Anyone that sets a long dated limit order will be at an disadvantage; this will encourage speed.

In this type of market mechanism, you'll see more trades move to OTC. If I find another individual that is willing to make a trade, I will do it off the exchange rather than on the exchange.

Lastly, please explain how you would be able to distinguish between an HFT trader and a regular trader? Does it make a difference? Why is it better for individual investors that they only trade with other investors?

>but they have an improved opportunity of making trades in the middle of the range that market makers would be willing to offer. This currently happens as it is. By SEC regulation, brokers are required to find the National Best Bid/Offer (NBBO) when you make a trade. In addition to this, brokers can perform Price Improvement actions and execute trades at better than NBBO (ie buy lower than ask/sell greater than bid). For example, ETrade has an 85.5% rate of price improvement. (https://us.etrade.com/e/t/activetrading/apptemplate?gxml=sca...)

Incidentally, I wrote a post about this market mechanism here: http://www.fatwallet.com/forums/finance/1004723/

Please forgive me if I am not understanding what your are suggesting, but a lot of what you are suggesting seems like it will not work in the real world.

Re: A High Frequency Trader's Apology, Pt 2

#192
post #190

Earlier quoted context omitted.

This is done in order to avoid intra-ETN transaction costs. There is nothing malicious or underhanded going on. This has always happened. Suppose you're in a room with your investor club and you want to buy 500 shares of AAPL. The evil "flash order" is akin to mentioning to your local group "hey guys I want to buy 500 shares of AAPL at $x, in case any of you want the other side of the transaction". If none of your lo…

I think the argument here (which I am not saying actually happens or can happen, as everything I know about this comes from reading this discussion) is that it is a little underhanded if you go "anyone want to be the other side of this transaction?" and someone in the room decides that you were a sucker for giving him the announce notice, opens his laptop, manages to find out that outside the room the going price is…

That may be the nature of the complaint, and it is definitely the underlying concern of the NBBO rules. But by saying "hey, anyone want to be the other side of this transaction" you're stating the price at which you'd find a trade beneficial.

This gets back to the nature of the market price. There is a fallacy that the market price is the price of the last trade. At any price, there is some combination of supply and demand.

Similarly, at any latency, transaction fee, etc., supply and demand may converge slightly differently (without NBBO rules). Since there is always the risk of trades occurring too far away from the price on the larger market, any ETN trader is going to figure out what his/her risk aversion is to this phenomenon and design his/her strategy accordingly.

For an HFT trader on an ETN w/o NBBO rules, it might make sense to buy a data feed from the NYSE to be sure to be aware of the up-to-the-second prices there. The NBBO rules benefit both the large mega-exchanges like the NYSE and also benefit other market participants who would have to buy a separate data feed to reduce risk, by strapping the cost of that additional data onto the backs of all the other participants, even those who would have a greater appetite for risk or whose strategies don't depend as much upon the ultimate depth at a given price.

What makes this even sillier is that for the small investor, trades on something like eTrade cost $20 each. If you're simply moving the investment between two investments that means two trades. This makes a LOT of strategies utter failures and not worth trying. The world of ETNs is just one more step of automation, dollars, and sophistication away from a simple eTrade account... hence its highly disruptive nature and the many startup hedge funds that have sprung up.

The genius of ETN creators was the realization that there is lots of depth provided by smaller, more niche players... to the point where many trades can be filled directly on the ETN for no fee. This opens up the door to many strategies that would simply have been impossible before, and combines the capital of each of these smaller players... each of whom has some exposure and who combined offer non-trivial depth... enough to take away volume from the major exchange monopolists.

This was not lost on the major exchanges who used their clout with regulators and journalists to institute the NBBO rule, to paint flash orders in a negative light, and generally sure up their monopoly positions against any competition.

Yes I said it, the major exchanges should be subject to a major anti-trust investigation and broken up. Of course, everyone (regulators included) is so afraid of upsetting the market that this will never happen... and if some other country opened up a market allowing such things, the US would ban Americans from using it.

Re: A High Frequency Trader's Apology, Pt 2

#193
post #94

Earlier quoted context omitted.

How can a market maker be the fastest without providing liquidity? An HFT market maker's willingness to buy XYZ from Alice at $10/shr to allow her out of her XYZ position is practically the definition of liquidity; its willingness to turn around and sell XYZ at $10.05/shr to Bob is more liquidity still. Alice wants to sell and can do so immediately and at a price she accepts; Bob wants to buy and can do so immediatel…

I think we are talking about two different things. Here is the scenario I imagine. Two market makers, Speedy and Big. They both decide to shave a penny off the spread, but Speedy is faster. The order book now looks like: SELL BIG - 1000 $600 SELL SPEEDY - 200 $600 ----- Buy SPEEDY - 200 $599 BUY BIG - 1000 $599 A buy and sell order comes in for 200 shares at market, and SPEEDY makes $200. BIG makes nothing. The probl…

Fine, SPEEDY gets that 200 share trade, now the order book looks like this:

SELL BIG - 1000 $600 ----- Buy SPEEDY - 200 $599 BUY BIG - 1000 $599

Another buy order at $600 comes in and BIG makes the trade.

Now the order book looks like this:

SELL BIG - 800 $600 ----- Buy SPEEDY - 200 $599 BUY BIG - 1000 $599

At this point, SPEEDY wants to get back in so he offers 200 shares @ $600. The Order book now looks like this:

Buy SPEEDY - 200 $600 SELL BIG - 800 $600 ----- Buy SPEEDY - 200 $599 BUY BIG - 1000 $599

So now SPEEDY is sitting behind BIG and has to wait until all 800 shares of his order soaks up the market.

So, where is the problem?

Re: A High Frequency Trader's Apology, Pt 2

#194

Earlier quoted context omitted.

I get that $0.10/share is significant, or I wouldn't have bothered posting. Why be annoyed at a process that isn't costing anyone anything significant? I also know that HFTs are taking money out of the equation, not adding money into the equation. If they weren't, they wouldn't be doing it -- and if the only value they're adding is reducing the time that a trade takes place by minutes or seconds, then I still submit…

I also know that HFTs are taking money out of the equation, not adding money into the equation. If they weren't, they wouldn't be doing it This assumption is questionable. There are a vast number of market participants who do loose money. The best start up example is the bias toward reporting companies who just got funding and not reporting all the companies that hit the dead pool. We don't really have a good idea on…

That seems massively unrealistic to me. It's safe to assume that HFT makes its participants a lot of money, for example because we know that they tend to spend a lot of money on hardware.

Re: A High Frequency Trader's Apology, Pt 2

#195
post #183

Earlier quoted context omitted.

There are also mandatory fill rates - i.e., if you don't fill at least 30% (or some such fraction) of the orders that are flashed to you, you get kicked out of the ELP program. When I read about these things it reminds me of when I was working for a gambling site a few years back. Arbitrary rules, designed to maximize profit for the bank.

The fill rate is not an arbitrary rule. The goal of ELP is to allow more orders to be filled on Direct Edge (i.e., not routed to INET/ARCA), thus saving Direct Edge customers routing fees (and making DE more money). If your ELP members aren't filling orders, then customers pay more to have their orders routed and DE makes less money.

I think the point about saving DE customers routing fees is the most important one here. If it weren't for DE's advantages (pricing, speed, lower fees) nobody would use it.

Re: A High Frequency Trader's Apology, Pt 2

#196

Earlier quoted context omitted.

I also know that HFTs are taking money out of the equation, not adding money into the equation. If they weren't, they wouldn't be doing it This assumption is questionable. There are a vast number of market participants who do loose money. The best start up example is the bias toward reporting companies who just got funding and not reporting all the companies that hit the dead pool. We don't really have a good idea on…

That seems massively unrealistic to me. It's safe to assume that HFT makes its participants a lot of money, for example because we know that they tend to spend a lot of money on hardware.

Do VCs all make money?

Mutual funds beat the bench?

Hegde funds?

Airlines? They spend a ton of money on fixed costs.

Some make money some do not.

Re: A High Frequency Trader's Apology, Pt 2

#197

Earlier quoted context omitted.

> hard to take anyone seriously who pines for the good old days of 1970's and 1980's trade execution. I've just read through the entire thread and I don't think anyone has suggested that.

"did major markets ever really have a huge problem with lack of liquidity, 20 or 30 years ago before HFT?"

I wasn't 'pining' for those days, I was barely even alive then. Just asking.

Re: A High Frequency Trader's Apology, Pt 2

#198

Earlier quoted context omitted.

I don't think that SomeCallMeTim understands that 0.10/share is a lot of money ($100,000) when a mutual fund is trading 1 million shares over 10 days. Now mulitply that by 60 holdings which are turned over 100% per year and you can see why pensions would want those mutual funds to save $6,000,000/year in liquidity costs. (Obviously mutual funds don't just do program trades, they also negotiate directly with each othe…

I get that $0.10/share is significant, or I wouldn't have bothered posting. Why be annoyed at a process that isn't costing anyone anything significant? I also know that HFTs are taking money out of the equation, not adding money into the equation. If they weren't, they wouldn't be doing it -- and if the only value they're adding is reducing the time that a trade takes place by minutes or seconds, then I still submit…

When speculators (HFTs) trade they either move prices in the right direction or they make a mistake and move prices in the wrong direction. When they move prices in the right direction, they provide a valuable price setting service to the market, and when that happens they also make a profit, in effect the market pays them for this service. When they move prices in the wrong direction they lose money, and they pay the fees of those other speculators who move prices in the right direction or they reduce costs for end producers and consumers. So in both cases the market benefits from the activity of speculators.

Re: A High Frequency Trader's Apology, Pt 2

#199

Earlier quoted context omitted.

A trojan informs the HFT of your order before you place it; it is thus front-running. Flash orders can't know your order before you place it - they just flash it to HFTs who fulfill it faster. The losers here are the slower market makers, not the retail trader. Equating flash orders and front-running does not make sense as the HFT doesn't know of the order before it is placed vis-à-vis the retail trader. The HFT appe…

>The HFT appears to have prevoyance vis-à-vis slower market makers And also because they have paid to get the information 0.5 second sooner, so that they could trade on their insider information.

[deleted]

Re: A High Frequency Trader's Apology, Pt 2

#200

Earlier quoted context omitted.

I don't think that SomeCallMeTim understands that 0.10/share is a lot of money ($100,000) when a mutual fund is trading 1 million shares over 10 days. Now mulitply that by 60 holdings which are turned over 100% per year and you can see why pensions would want those mutual funds to save $6,000,000/year in liquidity costs. (Obviously mutual funds don't just do program trades, they also negotiate directly with each othe…

I get that $0.10/share is significant, or I wouldn't have bothered posting. Why be annoyed at a process that isn't costing anyone anything significant? I also know that HFTs are taking money out of the equation, not adding money into the equation. If they weren't, they wouldn't be doing it -- and if the only value they're adding is reducing the time that a trade takes place by minutes or seconds, then I still submit…

>I also know that HFTs are taking money out of the equation, not adding money into the equation. If they weren't, they wouldn't be doing it

Either this logic, that profit is evidence of value destruction, is flawed or capitalism doesn't work.

You assume that the capital markets are a zero sum game. But by promoting liquidity HFTs make the markets (a) more attractive to play in, and, (b) cheaper for companies to finance themselves from.

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